JP2851906B2 - Optical modulation element and display device - Google Patents
Optical modulation element and display deviceInfo
- Publication number
- JP2851906B2 JP2851906B2 JP2074654A JP7465490A JP2851906B2 JP 2851906 B2 JP2851906 B2 JP 2851906B2 JP 2074654 A JP2074654 A JP 2074654A JP 7465490 A JP7465490 A JP 7465490A JP 2851906 B2 JP2851906 B2 JP 2851906B2
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- Prior art keywords
- thin film
- state
- liquid crystal
- birefringence
- optical modulation
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Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133528—Polarisers
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1347—Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells
- G02F1/13471—Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/137—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
- G02F1/139—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent
- G02F1/141—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent using ferroelectric liquid crystals
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/13363—Birefringent elements, e.g. for optical compensation
- G02F1/133638—Waveplates, i.e. plates with a retardation value of lambda/n
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2203/00—Function characteristic
- G02F2203/01—Function characteristic transmissive
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2203/00—Function characteristic
- G02F2203/02—Function characteristic reflective
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- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Mathematical Physics (AREA)
- Liquid Crystal (AREA)
- Devices For Indicating Variable Information By Combining Individual Elements (AREA)
- Electrochromic Elements, Electrophoresis, Or Variable Reflection Or Absorption Elements (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
Abstract
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は屈折率異方性を有する材料を用いた光学変調
素子、特に強誘電性カイラルスメクチック液晶を用いた
光学変調素子、及びそれを用いた表示装置に関する。The present invention relates to an optical modulator using a material having a refractive index anisotropy, in particular, an optical modulator using a ferroelectric chiral smectic liquid crystal, and an optical modulator using the same. Display device.
強誘電性カイラルスメクチック液晶を用いた光学変調
素子に於て、液晶の薄膜を互いに平行で、ごく薄い間隔
（例えば１〜２μｍ）を有する２枚の板の間に形成し、
該２枚の板の表面作用によって双安定な状態を作り出す
方式（SSFLC:表面安定型強誘電性液晶、Appl.Phys.Let
t.36（1980）899）は、その高速度応答性、メモリー性
等により様々な応用が期待されている。In an optical modulator using a ferroelectric chiral smectic liquid crystal, a thin film of liquid crystal is formed between two plates parallel to each other and having a very small interval (for example, 1 to 2 μm);
A method of creating a bistable state by the surface action of the two plates (SSFLC: surface stable ferroelectric liquid crystal, Appl. Phys. Let
t.36 (1980) 899) is expected to be used in various applications due to its high-speed response and memory properties.
前記双安定型の強誘電性液晶素子は、液晶の薄膜を挟
む両側の板の液晶薄膜側にラビング等により形成される
配向作用面の軸方向（ラビング方向等）に対し、ある一
定角度異なった方向に於て２つの安定状態を示す。この
安定状態間の1/2角度をチルト角（以後θｃと表す）と
いう。この液晶素子の液晶薄膜面に対して垂直な方向に
電圧を印加すると、強誘電性液晶は一方の安定状態から
他方の安定状態へ移る。この変化は屈折率異方性を有す
る材料の光学軸を角度２θｃだけ回転させることに対応
している。従って、1/2波長板の作用に相当する厚みを
有する前記強誘電性液晶素子に対し、偏光光が入射した
場合、双安定の２つの状態による入射偏光光に対する偏
光回転作用は互いに４θｃだけ異なる。クロスニコル或
は平行ニコル配置の偏光素子（偏光板等）で前記強誘電
性液晶素子を挟むと ４θｃ＝90゜（θｃ＝22.5゜） の時、２つの安定状態間に於ける透過光量のオン・オフ
比（透過率比、コントラスト）は、最も高くなる。The bistable ferroelectric liquid crystal element has a certain angle different from the axial direction (rubbing direction, etc.) of an alignment action surface formed by rubbing or the like on the liquid crystal thin film side of the two plates sandwiching the liquid crystal thin film. It shows two stable states in the direction. The half angle between the stable states is called a tilt angle (hereinafter, referred to as θc). When a voltage is applied in a direction perpendicular to the liquid crystal thin film surface of the liquid crystal element, the ferroelectric liquid crystal shifts from one stable state to the other. This change corresponds to rotating the optical axis of the material having the refractive index anisotropy by the angle 2θc. Therefore, when polarized light is incident on the ferroelectric liquid crystal element having a thickness corresponding to the action of the half-wave plate, the polarization rotating actions on incident polarized light in the two bistable states are different from each other by 4θc. . When the ferroelectric liquid crystal element is sandwiched between polarizing elements (polarizing plates or the like) arranged in crossed Nicols or parallel Nicols, when 4θc = 90 ° (θc = 22.5 °), the amount of transmitted light between two stable states is turned on. -The off ratio (transmittance ratio, contrast) is highest.
しかしながら、前記チルト角θｃは液晶材料や配向作
用面の特性に強く依存しており、未だ十分なチルト角θ
ｃを有する強誘電性液晶素子は実現されておらず、光学
変調素子として用いる場合、その変調度は不十分であっ
た。However, the tilt angle θc strongly depends on the characteristics of the liquid crystal material and the orientation action surface, and the tilt angle θc is still insufficient.
The ferroelectric liquid crystal element having c has not been realized, and when used as an optical modulation element, the degree of modulation was insufficient.
本発明の目的は、高コントラストな表示を実現する光
学変調素子及びそれを用いた表示装置を提供することに
ある。An object of the present invention is to provide an optical modulation element for realizing a high-contrast display and a display device using the same.
本発明の別の目的は、高透過率特性を達した光学変調
素子及びそれを用いた表示装置を提供することにある。Another object of the present invention is to provide an optical modulation element having high transmittance characteristics and a display device using the same.
本発明は、 a.偏光子、 b.印加された電圧に応じて、前記偏光子によって偏光さ
れた光線に複屈折を生じさせる第１の状態と該光線に複
屈折を生じさせない第２の状態とを生じる薄膜であっ
て、該薄膜が該第１の状態を生じている時に、1/2波長
板として機能する膜厚である第１の薄膜、 c.前記第１の薄膜の第１の状態を通過した光線に複屈折
を生じさせ、前記第１の薄膜の第２の状態を通過した光
線に複屈折を生じさせない薄膜であって、前記第１の薄
膜が前記第１の状態である時に1/4波長板として機能す
る膜厚である第２の薄膜、並びに、 d.前記第２の薄膜を通過した光線を反射し、該光線を再
度該第２の薄膜に入射させる反射手段、 を有する光学変調素子、 及び、該光学変調素子を用いた表示装置、に第１の特徴
を有しており、 a.偏光子、 b.印加された電圧に応じて、前記偏光子によって偏光さ
れた光線に複屈折を生じさせる第１の状態と該光線に複
屈折を生じさせない第２の状態とを生じる薄膜であっ
て、該薄膜が該第１の状態を生じている時に、1/2波長
板として機能する膜厚である第１の薄膜、 c.前記第１の薄膜の第１の状態を通過した光線に複屈折
を生じさせ、前記第１の薄膜の第２の状態を通過した光
線に複屈折を生じさせない薄膜であって、前記第１の薄
膜が前記第１の状態である時に1/2波長板として機能す
る膜厚である第２の薄膜、 d.複屈折を生じて前記第２の薄膜を通過した光線に複屈
折を生じさせ、複屈折を生じることなく前記第２の薄膜
を通過した光線に複屈折を生じさせない薄膜である第３
の薄膜、並びに、 e.検光子 を有する光学変調素子、に第２の特徴を有している。The present invention provides: a. A polarizer; b. A first state in which a light beam polarized by the polarizer causes birefringence according to an applied voltage, and a second state in which the light beam does not cause birefringence. A first thin film having a thickness functioning as a half-wave plate when the thin film is in the first state; c. A first thin film of the first thin film A birefringent light beam that has passed through a state, and does not cause birefringence of a light beam that has passed through a second state of the first thin film, wherein the first thin film is in the first state. A second thin film having a thickness sometimes functioning as a quarter-wave plate, and d. Reflecting means for reflecting a light beam that has passed through the second thin film and causing the light beam to again enter the second thin film; An optical modulator having the following features: and a display device using the optical modulator, having the first feature, a. Polarizer b. a thin film that, in response to an applied voltage, produces a first state in which light polarized by the polarizer causes birefringence and a second state in which the light does not produce birefringence, A first thin film having a thickness functioning as a half-wave plate when the thin film is in the first state; c. Birefringence is imparted to a light beam passing through the first state of the first thin film. The first thin film is a thin film that does not cause birefringence in a light beam that has passed through the second state of the first thin film, and functions as a half-wave plate when the first thin film is in the first state. A second thin film having a film thickness; d. Birefringence is caused to cause birefringence in a light beam passing through the second thin film, and birefringence is caused to a light beam passing through the second thin film without causing birefringence. Third, which is a thin film that does not cause
And the optical modulator having the analyzer has the second feature.
〔実施例〕 第４図は、本発明の機能及び作用を説明するための模
式図である。Embodiment FIG. 4 is a schematic diagram for explaining the function and operation of the present invention.
第４図（Ａ）は配向軸方向をそろえた同一の双安定強
誘電性液晶の薄膜11と13と1/2波長板12からなり、上記
２つの強誘電性液晶の薄膜11と13の片方の安定状態（第
１の安定状態）に於ける液晶分子の長軸方向n1、n3（よ
り厳密には液晶の屈折率楕円体の一主軸方向）と、1/2
波長板12の屈折率楕円体の一主軸方向n2の３者は同じ方
向を向いている。３枚の薄膜11、12及び13は、互いに平
行であり、かつ各々は主波長に対して1/2波長板相当の
作用を成す。本構成の液晶素子に対し、n1、n2、n3に平
行ない振動電場をもつ電磁波Ｅλが入射した場合、薄膜
11、12及び13の通過後の振動電場E1、E2、E3及び出射光
Eoutの振動電場の方向は変化しない。（ＥλE1E2
Eout（＝E3）） 一方、第４図（Ｂ）は、双安定強誘電性液晶の薄膜11
と13を他方の安定状態（第２の安定状態）に保った場合
の構成を示しており、強誘電性液晶の薄膜11と13の液晶
長軸方向は入射光Einの振動電場の方向に対して２θｃ
だけ同じ方向に回転している。まず、第１の液晶薄膜11
を通過した光の電場E1は入射光に対して４θｃだけ回転
する。次に、1/2波長板12を通過した光の電場E2は屈折
率の１出軸n2に対して−４θｃだけ回転した方向とな
る。最後にE2に対して６θｃ（＝４θｃ＋２θｃ）だけ
回転した方向に液晶分子長軸n3をもつ第２の液晶薄膜13
を通過した光の電場E3（＝Eout）は液晶分子長軸n3に対
して、６θｃだけ回転した方向となる。従って、出射光
の電場方向は入射光の電場方向に対して８θｃ（＝２θ
ｃ＋６θｃ）だけ回転することになり、液晶薄膜の１つ
だけの場合と比較して、２倍の偏光回転が可能となるこ
とを示している。即ち、 θｃ＝11.25゜ のチルト角θｃで、透過光量のオン・オフ比（透過率
比、コントラスト）を最大にすることができる。FIG. 4 (A) is composed of the same bistable ferroelectric liquid crystal thin films 11 and 13 aligned in the direction of the alignment axis and a half-wave plate 12, and one of the two ferroelectric liquid crystal thin films 11 and 13 is used. In the stable state (first stable state) of the liquid crystal molecules, the major axis directions n 1 and n 3 (more strictly, one principal axis direction of the refractive index ellipsoid of the liquid crystal) and 1/2
3's one principal axis direction n 2 of the refractive index ellipsoid of the wave plate 12 is oriented in the same direction. The three thin films 11, 12, and 13 are parallel to each other, and each function as a half-wave plate with respect to the main wavelength. When an electromagnetic wave E λ having an oscillating electric field not parallel to n 1 , n 2 , and n 3 is incident on the liquid crystal element having this configuration, a thin film is formed.
Oscillating electric fields E 1 , E 2 , E 3 and emitted light after passing through 11, 12 and 13
The direction of the oscillating electric field at E out does not change. (E λ E 1 E 2
E out (= E 3 ) On the other hand, FIG. 4B shows a thin film 11 of a bistable ferroelectric liquid crystal.
And 13 are kept in the other stable state (second stable state). The long axis direction of the ferroelectric liquid crystal thin films 11 and 13 is in the direction of the oscillating electric field of the incident light Ein. 2θc
Only rotate in the same direction. First, the first liquid crystal thin film 11
Electric field E 1 of the light passing through the can rotates by 4θc with respect to the incident light. Then, the electric field E 2 in the light passing through the 1/2-wavelength plate 12 is a direction rotated by -4θc per Dejiku n 2 refractive index. Finally 6θc against E 2 (= 4θc + 2θc) a second liquid crystal film 13 having a liquid crystal molecular long axis n 3 only rotated direction
The electric field E 3 (= E out ) of the light passing through is in a direction rotated by 6θc with respect to the long axis n 3 of the liquid crystal molecule. Therefore, the electric field direction of the outgoing light is 8θc (= 2θ) with respect to the electric field direction of the incident light.
c + 6θc), which indicates that the polarization can be rotated twice as compared with the case where only one liquid crystal thin film is used. That is, at the tilt angle θc of θc = 11.25 °, the on / off ratio (transmittance ratio, contrast) of the transmitted light amount can be maximized.
この際、本発明では、液晶薄膜11、及び13の膜は、好
ましくは1.2μｍ〜1.6μｍである。特に液晶薄膜11及び
13としてカイラルスメクチック液晶を用いると、1.2μ
ｍ〜1.6μｍの膜厚の時に、カイラルスメクチック液晶
が固有するらせん構成の形成が抑制されて、双安定性を
発現する配向状態が得られる。At this time, in the present invention, the thickness of the liquid crystal thin films 11 and 13 is preferably 1.2 μm to 1.6 μm. In particular, the liquid crystal thin film 11 and
If a chiral smectic liquid crystal is used as 13, 1.2 μm
When the thickness is from m to 1.6 μm, the formation of a helical structure inherent to the chiral smectic liquid crystal is suppressed, and an alignment state exhibiting bistability is obtained.
第１図は本発明を投写型表示装置に適用した場合の実
施例の構成を示したものであり、第２図は光学変調素子
部の作用の概略説明図。第３図はその詳細構成を示した
ものである。FIG. 1 shows a configuration of an embodiment in which the present invention is applied to a projection display device, and FIG. 2 is a schematic explanatory view of the operation of an optical modulation element. FIG. 3 shows the detailed configuration.
第１図に於て、不定偏光光を発する光源16より発光し
た光は反射笠17で反射され、コンデンサレンズ18でコリ
メートされた後、偏光ビームスプリツタ19に入射し、偏
光ビームスプリツタ19に対するＰ偏光成分は透過し、Ｓ
偏光成分が垂直方向に反射される。In FIG. 1, light emitted from a light source 16 that emits indefinitely polarized light is reflected by a reflector 17 and collimated by a condenser lens 18 before being incident on a polarizing beam splitter 19 and transmitted to the polarizing beam splitter 19. The P-polarized component is transmitted and S
The polarization component is reflected in the vertical direction.
上記Ｓ偏光成分は1/2波長板相当の双安定強誘電性液
晶の薄膜11、1/4波長板14を通過して反射板15によって
反射され、再び1/4波長板14、双安定強誘電性液晶の薄
膜11を通過する。The S-polarized light component passes through a thin film 11 of bistable ferroelectric liquid crystal equivalent to a half-wave plate, is reflected by a reflector 15 after passing through a quarter-wave plate 14, and is again reflected by the quarter-wave plate 14, It passes through a thin film 11 of dielectric liquid crystal.
上記Ｓ偏光成分は、双安定性強誘電性液晶薄膜11の状
態に応じてＰ偏光成分を生じ、再び偏光ビームスプリツ
タ19に入射する際、Ｓ偏光成分は反射され、透過したＰ
偏光成分が投写レンズ10により、不図示の画像投影用ス
クリーン面上に結像投影される。偏光ビームスプリツタ
19は本構成に於ては偏光子・検光子両者を兼ねている。The S-polarized light component, resulting P-polarized light component in accordance with the state of the bistable ferroelectric liquid crystal film 11, when incident on the polarization beam splitter 19 again, the S-polarized light component is reflected, transmitted through P
The polarization component is image-formed and projected by the projection lens 10 on an image projection screen surface (not shown). Polarizing beam splitter
Reference numeral 19 serves as both a polarizer and an analyzer in the present configuration.
以下、第２図を用いて説明する。第２図（Ａ）は反射
前の偏光の状態、第２図（Ｂ）は反射後の偏光の状態を
表している。第２図に於て、入射光は振動電場Einをも
つ直線偏光光である。強誘電性液晶11の長軸がn1が1/4
波長板14の長軸n4及びEinと平行な片方の安定状態（第
１の安定状態）に於ては偏光回転は起こらない。一方、
第２図に示した如く、液晶11の長軸n1が２θｃだけEin
に対して回転した状態に於ては、まず、液晶薄膜11を通
過した光の電場E1は入射光に対して４θｃだけ回転する
（第２図（Ａ））。次に1/4波長板14を通過した光の電
場E2は円偏光となって（第２図（Ａ））、反射板15によ
って反射され、再び1/4波長板14に入射する（第２図
（Ｂ））。1/4波長板14を通過した電場E3は、1/4波長板
14の屈折率の１主軸n4に対して−４θｃだけ回転した方
向となる（第２図（Ｂ））。最後にE3に対して６θｃ
（＝４θｃ＋２θｃ）だけ回転した方向に液晶分子長軸
n1をもつ液晶薄膜11を通過した光の電場E4（＝Eout）は
液晶分子長軸に対して６θｃだけ回転した方向となる
（第２図（Ｂ））。Hereinafter, description will be made with reference to FIG. FIG. 2A shows the state of polarized light before reflection, and FIG. 2B shows the state of polarized light after reflection. At a second figure, the incident light is linearly polarized light having a vibrating electric field E in. Major axis n 1 of the ferroelectric liquid crystal 11 is 1/4
Polarization rotation At a parallel one stable state and long axis n 4 and E in the wave plate 14 (first stable state) does not occur. on the other hand,
As shown in Figure 2, the major axis n 1 of the liquid crystal 11 only 2Shitashi Ein
Te is at a state of being rotated relative to, firstly, the electric field E 1 of the light passing through the liquid crystal film 11 is rotated by 4θc with respect to the incident light (FIG. 2 (A)). Electric field E 2 in the light passing through the quarter-wave plate 14 then is turned into circularly polarized light (FIG. 2 (A)), is reflected by the reflection plate 15, and enters again the quarter-wave plate 14 (second 2 (B). Electric field E 3 passing through quarter-wave plate 14 is a quarter-wave plate
14 the direction rotated by -4θc per spindle n 4 of the refractive index of the (second view (B)). Finally 6θc to the E 3
Liquid crystal molecule long axis in the direction rotated by (= 4θc + 2θc)
The electric field E 4 (= E out ) of the light passing through the liquid crystal thin film 11 having n 1 is in a direction rotated by 6θc with respect to the long axis of the liquid crystal molecules (FIG. 2 (B)).
従って出射光の電場方向は入射光の電場方向に対して
８θｃ（＝２θｃ＋６θｃ）だけ回転することになる。
この様に反射型構成とすることにより１つの変調素子で
２倍の偏光回転角が得られる。Therefore, the electric field direction of the emitted light rotates by 8θc (= 2θc + 6θc) with respect to the electric field direction of the incident light.
With such a reflection type configuration, a double polarization rotation angle can be obtained with one modulation element.
第３図は、第２図に示した部分をより詳細に示したも
のであり、入射光側より、透明なガラス基板301（厚み
約1mm）、電極作用をする透明なITO膜302（厚み約1500
Å）、対向電極との短絡を避ける為の絶縁膜303（厚み
約1200Å）、液晶を配向させる為のラビング処理を施し
たポリイミド膜304（厚み約200Å）、不図示の径１〜２
μｍのビーズにより保持された間隙に注入された液晶薄
膜305、ポリイミド膜304と同様のポリイミド膜306（厚
み約200Å）、ポリイミド膜306の基板となる薄い透明層
307（例えばガラス板）、屈折率異方性をもち1/4波長板
相当の作用を行なう高分子液晶薄膜308（厚み１μｍ以
下）、高分子液晶の配向を容易にする為にラビング処理
を施したポリイミド膜309（厚み約200Å）,ITO膜302に
対する対向電極作用及び、光の反射作用を兼ねたアルミ
ニウム蒸着膜310（厚み数μｍ）、及びガラス基板311
（厚み約1mm）の各部から構成されている。FIG. 3 shows the portion shown in FIG. 2 in more detail. From the incident light side, a transparent glass substrate 301 (thickness of about 1 mm) and a transparent ITO film 302 serving as an electrode (thickness of about 1 mm) are formed. 1500
I), an insulating film 303 (about 1200 mm thick) to avoid short circuit with the counter electrode, a rubbed polyimide film 304 (about 200 mm thick) for aligning the liquid crystal, diameters 1 to 2 (not shown)
Liquid crystal thin film 305 injected into the gap held by μm beads, polyimide film 306 (about 200 mm thick) similar to polyimide film 304, thin transparent layer serving as substrate for polyimide film 306
307 (for example, a glass plate), a polymer liquid crystal thin film 308 (thickness of 1 μm or less) having a refractive index anisotropy and acting like a quarter-wave plate, and a rubbing treatment for facilitating alignment of the polymer liquid crystal. A polyimide film 309 (thickness of about 200 mm), an aluminum vapor-deposited film 310 (thickness of several μm) having a counter electrode function on the ITO film 302 and a light reflection function, and a glass substrate 311.
(About 1mm thick).
本光学変調素子は、ガラス基板301、311上に必要な層
を順次形成した後、両者の間隙304に液晶材料を注入
し、更に熱処理等により双安定強誘電状態とする。出射
光の偏光状態の変調は電極302、310への印加信号により
行なう。In the present optical modulation element, after necessary layers are sequentially formed on glass substrates 301 and 311, a liquid crystal material is injected into a gap 304 between the two, and a bistable ferroelectric state is formed by heat treatment or the like. The modulation of the polarization state of the emitted light is performed by a signal applied to the electrodes 302 and 310.
本光学変調素子は複数画素を独立に変調することによ
り容易に画像表示に適用可能である。例えば、ITO電極3
02及びアルミニウム電極310を各々短冊型の複数独立の
電極とし、しかも両者を互いに直交させて、マトリクス
型の構成とした場合（いわゆる単純マトリクス駆動）で
ある。この様にして画像表示を行なう場合、同じ画面サ
イズに於て解像力を向上させる為には１画素当りのサイ
ズを小さくする必要があり、投写型表示装置の如く、小
型の液晶表示素子を用いる場合例えば対角３インチに於
て１画素約□60μｍ（EDTV用）となる。The optical modulation element can be easily applied to image display by modulating a plurality of pixels independently. For example, ITO electrode 3
This is a case in which each of the 02 and the aluminum electrode 310 is a plurality of strip-shaped independent electrodes, and both are orthogonal to each other to form a matrix type configuration (so-called simple matrix drive). When an image is displayed in this manner, it is necessary to reduce the size per pixel in order to improve the resolving power in the same screen size, and when a small liquid crystal display element is used as in a projection display device. For example, one pixel is about 60 μm (for EDTV) at a diagonal of 3 inches.
本発明の素子構成に於ては1/4波長板として水晶、雲
母、延伸フイルム等に比べ屈折率異方性（Δｎ）が格段
に大きい（１〜２桁）高分子液晶（Δｎ〜0.2）を用い
ることにより、1/4波長板の厚みを１μｍ以下に抑える
ことができる。In the element structure of the present invention, a polymer liquid crystal (Δn-0.2) having a remarkably larger refractive index anisotropy (Δn) (1 to 2 digits) as compared with quartz, mica, stretched film, etc. as a 波長 wavelength plate The thickness of the quarter-wave plate can be suppressed to 1 μm or less by using.
また、ポリイミド膜306の基板となるガラス板307は素
子保持強度として十分な厚みをもつガラス基板311上に
構成されるので非常に薄いガラス材を用いることができ
る。画素電極302、310間の他の層は従来構成に於ても１
画素サイズに比べて十分に薄い為、高分子液晶による1/
4波長板308、及び極薄のガラス板307は実効開口率の向
上、画像間クロストークの防止に対して大きな効果を発
揮することができる。Further, since the glass plate 307 serving as the substrate of the polyimide film 306 is formed on the glass substrate 311 having a sufficient thickness for element holding strength, a very thin glass material can be used. The other layers between the pixel electrodes 302 and 310 are 1 in the conventional configuration.
Because it is sufficiently thin compared to the pixel size, 1 /
The four-wavelength plate 308 and the extremely thin glass plate 307 can exert a great effect on improving the effective aperture ratio and preventing crosstalk between images.
また、本発明では、ITO膜302とアルミニウム蒸着膜31
0とで形成した一対の電極間に正極性パルスと負極性パ
ルスとを選択的に駆動回路312から印加し、強誘電性液
晶で形成した液晶薄膜305に対して、正極性パルス又は
負極性パルスに応じて、第１の安定状態又は第２の安定
状態に配向させることができる。Further, in the present invention, the ITO film 302 and the aluminum deposition film 31
A positive pulse and a negative pulse are selectively applied from the driving circuit 312 between the pair of electrodes formed by the positive and negative electrodes, and the positive or negative pulse is applied to the liquid crystal thin film 305 formed of ferroelectric liquid crystal. Can be oriented to the first stable state or the second stable state.
本発明に用いる高分子液晶薄膜308の例としては、ネ
マチツク高分子液晶（PAfB） が挙げられ、 ラビング処理を施したポリイミド膜（SE−100、厚み500
Å）309上に、上記液晶のシクロヘキサノン溶液（10wt
％）をスピンコートにより塗布し、乾燥した後、熱処理
（100℃、２〜３時間）を施すことにより、数千Åの厚
みをもつ均一な配向方向をもつ高分子液晶が形成され
た。An example of the polymer liquid crystal thin film 308 used in the present invention is a nematic polymer liquid crystal (PAfB). Rubbed polyimide film (SE-100, thickness 500
Ii) On the 309, a cyclohexanone solution of the above liquid crystal (10wt
%) Was applied by spin coating, dried, and then subjected to a heat treatment (100 ° C., 2 to 3 hours) to form a polymer liquid crystal having a thickness of several thousand Å and a uniform alignment direction.
なお、本実施例では、入射偏光軸Ein、液晶片方の安
定状態の分子長軸n1、1/4波長板の一主軸n4を一致させ
ることにより、片方の安定状態では主波長以外でも位相
差ずれのない状態を少なくとも１つ実現している。従っ
て、クロスニコル時は黒の透過率を低く抑えコントラス
ト比を高くでき、平行ニコル時は白状態の色相変化を抑
えることができる。In this embodiment, the incident polarization axis E in , the long axis of the molecule n 1 of one of the stable states of the liquid crystal, and the main axis n 4 of the quarter-wave plate are matched, so that in one of the stable states other than the main wavelength. At least one state without a phase difference is realized. Therefore, in the case of crossed Nicols, the transmittance of black can be reduced and the contrast ratio can be increased, and in the case of parallel Nicols, the change in hue of the white state can be suppressed.
しかしながら本来は、３者の軸方向の組合わせに制限
なく、いかなる組合わせに於ても少なくとも主波長に対
しては０％、100％の変調可能である。この際、高分子
液晶薄膜308の膜厚としては、0.6μｍ〜0.8μｍが好ま
しい。However, originally, there is no limitation on the combination of the three components in the axial direction, and in any combination, 0% and 100% modulation can be performed on at least the main wavelength. At this time, the thickness of the polymer liquid crystal thin film 308 is preferably 0.6 μm to 0.8 μm.
第５図は、本発明の別の実施態様を表わしている。 FIG. 5 shows another embodiment of the present invention.
第３図と同一符号は、同一部材である。本実施例で
は、1/4反射板に相当する膜厚に設定されている高分子
液晶薄膜308と液晶薄膜305との間にラビング処理したポ
リイミド配向膜と、SiO、SiO2、TiO2などの絶縁材で形
成した絶縁膜512と、電極として使用するITO膜513とが
配置されている。駆動回路312からITO膜302と513間に正
極性パルスと負極性パルスが印加される。The same reference numerals as those in FIG. 3 denote the same members. In the present embodiment, a polyimide alignment film rubbed between a polymer liquid crystal thin film 308 and a liquid crystal thin film 305 set to a film thickness corresponding to a quarter reflector, and SiO, SiO 2 , TiO 2 etc. An insulating film 512 formed of an insulating material and an ITO film 513 used as an electrode are provided. A positive pulse and a negative pulse are applied between the ITO films 302 and 513 from the drive circuit 312.
本実施例によれば、電極間距離が短くなる為、必要な
印加電圧を小さくできる。図中のアルミニウム蒸着膜31
0が反射膜として機能している。According to this embodiment, since the distance between the electrodes is reduced, the required applied voltage can be reduced. Aluminum deposited film 31 in the figure
0 functions as a reflective film.
第６図は、本発明の別の実施態様を表している。 FIG. 6 shows another embodiment of the present invention.
第３図及び第５図と同一符号は、同一部材である。本
実施例では、セル内に薄膜トランジスタ（TFT）を用い
たアクテイブマトリクス駆動素子を用いたものである。
従って、図中の符号で示した部材は、下記のとおりであ
る。The same reference numerals as those in FIGS. 3 and 5 denote the same members. In this embodiment, an active matrix driving element using a thin film transistor (TFT) in a cell is used.
Therefore, the members indicated by reference numerals in the drawing are as follows.
614…透明なITO電極 615…絶縁膜（SiO2など） 616…ラビング処理したポリイミド膜 617…TFTのゲート 618…窒化シリコン絶縁膜（ゲート絶縁膜） 619…TFTのソース 620…TFTのドレイン 以上、実施例に沿って本発明を説明したが、本発明に
おいては、下記の点で有効に適用することができる。614… Transparent ITO electrode 615… Insulating film (SiO 2 etc.) 616… Rubbed polyimide film 617… TFT gate 618… Silicon nitride insulating film (gate insulating film) 619… TFT source 620… TFT drain Although the present invention has been described with reference to the embodiments, the present invention can be effectively applied in the following points.
（１）上述の実施例では、強誘電性液晶素子を用いた
が、電界により複屈折性を抑制する素子を用いた場合一
般的に有効である。(1) In the above embodiment, a ferroelectric liquid crystal element was used, but it is generally effective to use an element that suppresses birefringence by an electric field.
（２）適用装置例として、投写型表示装置の１例を示し
たが、本構成に限定する必要はなく、更に直視型表示装
置に於ても有効である。(2) Although an example of a projection display device has been described as an example of an application device, the present invention is not limited to this configuration, and is also effective in a direct-view display device.
（３）変調度として、０％、100％の２点のみ示した
が、中間の偏光回転角を用いた濃度階調、０％、100％
の面積比を制御する面積階調、或はその混合方式等の階
調制御方式に於ても有効である。(3) Although only two points of 0% and 100% are shown as the modulation degree, the density gradation using the intermediate polarization rotation angle, 0% and 100%
This is also effective in a gray scale control method such as an area gray scale for controlling the area ratio or a mixed method thereof.
（４）上述の実施例では、1/4波長板として配向処理を
施した高分子液晶を用いたが、水晶、雲母、延伸フイル
ム等を用いても良く、少なくとも液晶変調素子が１ケで
済むことによる効果は失われない。(4) In the above embodiment, the polymer liquid crystal subjected to the alignment treatment was used as the quarter-wave plate, but quartz, mica, stretched film or the like may be used, and at least one liquid crystal modulation element is required. The effect of this is not lost.
本発明によれば、 （１）双安定性強誘電性液晶素子に於て、小さなチルト
角θｃの材料でもコントラスト比の大きい変調が可能と
なる。According to the present invention, (1) in a bistable ferroelectric liquid crystal device, modulation with a large contrast ratio is possible even with a material having a small tilt angle θc.
（２）反射型構成とすることにより、簡単な素子構成に
よって実現でき、この結果製造プロセスの簡略化が可能
となった。(2) By adopting the reflection type configuration, it can be realized with a simple element configuration, and as a result, the manufacturing process can be simplified.
（３）高分子液晶を1/4波長板とすることにより、実効
開口率向上と画素間クロストーク（他画素への光のもれ
込み）の減少を実現できた。特に、 屈折率異方性が通常の異方性物質（水晶、雲母、延伸
フイルム等）に比べ大きいので、厚みを薄くでき、開口
率低下、画素間クロストークが緩和された。(3) By using a polymer liquid crystal as a quarter-wave plate, it was possible to improve the effective aperture ratio and reduce crosstalk between pixels (light leakage into other pixels). In particular, since the refractive index anisotropy is larger than ordinary anisotropic substances (quartz, mica, stretched film, etc.), the thickness can be reduced, the aperture ratio decreases, and the crosstalk between pixels is reduced.
流動性の大きい高温状態に於て、配向させた後、配向
の安定する温度域で使用することができる為、同じく屈
折率異方性の大きい低分子液晶よりも扱いが容易となっ
た。After alignment, it can be used in a temperature range where the alignment is stable in a high-temperature state with high fluidity, so that it is easier to handle than a low-molecular liquid crystal having a large refractive index anisotropy.
第１図は、本発明の表示装置を示す断面図である。 第２図（Ａ）及び（Ｂ）は、本発明の機能と作用を模式
的に説明するための斜視図である。 第３図は、本発明の光学変調素子の断面図である。 第４図（Ａ）及び（Ｂ）は、本発明の別の機能と作用を
模式的に説明するための斜視図である。 第５図及び第６図は、本発明の別の光学変調素子の断面
図である。FIG. 1 is a sectional view showing a display device of the present invention. 2 (A) and 2 (B) are perspective views for schematically explaining the function and operation of the present invention. FIG. 3 is a sectional view of the optical modulation element of the present invention. FIGS. 4A and 4B are perspective views for schematically explaining another function and operation of the present invention. 5 and 6 are cross-sectional views of another optical modulation device of the present invention.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) G02F 1/1335 G02F 1/01──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 6 , DB name) G02F 1/1335 G02F 1/01
Claims (26)
れた光線に複屈折を生じさせる第１の状態と該光線に複
屈折を生じさせない第２の状態とを生じる薄膜であっ
て、該薄膜が該第１の状態を生じている時に、1/2波長
板として機能する膜厚である第１の薄膜、 c.前記第１の薄膜の第１の状態を通過した光線に複屈折
を生じさせ、前記第１の薄膜の第２の状態を通過した光
線に複屈折を生じさせない薄膜であって、前記第１の薄
膜が前記第１の状態である時に1/4波長板として機能す
る膜厚である第２の薄膜、並びに、 d.前記第２の薄膜を通過した光線を反射し、該光線を再
度該第２の薄膜に入射させる反射手段、 を有する光学変調素子。1. A first state in which a light beam polarized by the polarizer produces birefringence in accordance with an applied voltage, and a second state in which the light beam does not produce birefringence in response to an applied voltage. A first thin film having a thickness that functions as a half-wave plate when the thin film is in the first state; c. A first thin film of the first thin film A birefringence is generated in the light beam that has passed through the state, and the birefringence is not generated in the light ray that has passed through the second state of the first thin film, wherein the first thin film is in the first state. A second thin film having a thickness functioning as a quarter-wave plate at one time; and d. Reflecting means for reflecting a light beam passing through the second thin film and causing the light beam to be incident on the second thin film again. An optical modulation element comprising:
請求項１記載の光学変調素子。2. The optical modulation device according to claim 1, wherein said first thin film is a thin film made of liquid crystal.
る請求項２記載の光学変調素子。3. The optical modulator according to claim 2, wherein the liquid crystal is a chiral smectic liquid crystal.
である請求項１記載の光学変調素子。4. The optical modulation element according to claim 1, wherein said second thin film is a thin film made of a polymer liquid crystal.
極を有する請求項１記載の光学変調素子。5. The optical modulation device according to claim 1, further comprising a pair of electrodes arranged with the first thin film interposed therebetween.
極性パルスとを選択的に印加する電界印加手段を有する
請求項５記載の光学変調素子。6. An optical modulation device according to claim 5, further comprising an electric field applying means for selectively applying one polarity pulse and the other polarity pulse between said pair of electrodes.
る請求項１記載の光学変調素子。7. The optical modulation device according to claim 1, wherein the thickness of the first thin film is 1.2 to 1.6 μm.
る請求項１記載の光学変調素子。8. The optical modulation device according to claim 1, wherein the thickness of the second thin film is 0.6 to 0.8 μm.
前記第２の薄膜の間に配置されている請求項５記載の光
学変調素子。9. The optical modulation element according to claim 5, wherein one of said pair of electrodes is disposed between said first thin film and said second thin film.
液晶からなり、前記第２の薄膜が高分子液晶からなる請
求項９記載の光学変調素子。10. An optical modulation device according to claim 9, wherein said first thin film is made of a chiral smectic liquid crystal, and said second thin film is made of a polymer liquid crystal.
方極性パルスとを選択的に印加する電界印加手段を有す
る請求項９記載の光学変調素子。11. The optical modulation element according to claim 9, further comprising electric field applying means for selectively applying one polarity pulse and the other polarity pulse between said pair of electrodes.
れた光線に複屈折を生じさせる第１の状態と該光線に複
屈折を生じさせない第２の状態とを生じる薄膜であっ
て、該薄膜が該第１の状態を生じている時に、1/2波長
板として機能する膜厚である第１の薄膜、 c.前記第１の薄膜の第１の状態を通過した光線に複屈折
を生じさせ、前記第１の薄膜の第２の状態を通過した光
線に複屈折を生じさせない薄膜であって、前記第１の薄
膜が前記第１の状態である時に1/2波長板として機能す
る膜厚である第２の薄膜、 d.複屈折を生じて前記第２の薄膜を通過した光線に複屈
折を生じさせ、複屈折を生じることなく前記第２の薄膜
を通過した光線に複屈折を生じさせない薄膜である第３
の薄膜、並びに、 e.検光子 を有する光学変調素子。12. A first state in which a light beam polarized by the polarizer causes birefringence according to an applied voltage, and a second state in which the light beam does not cause birefringence according to an applied voltage. A first thin film having a thickness that functions as a half-wave plate when the thin film is in the first state; c. A first thin film of the first thin film A birefringence is generated in the light beam that has passed through the state, and the birefringence is not generated in the light ray that has passed through the second state of the first thin film, wherein the first thin film is in the first state. A second thin film having a thickness functioning as a half-wave plate at one time; d. Causing birefringence to cause birefringence in a light beam that has passed through the second thin film, without causing birefringence. The third film, which does not cause birefringence in the light beam passing through the second film,
And an optical modulator having an analyzer.
る請求項12記載の光学変調素子。13. The optical modulation element according to claim 12, wherein said first thin film is a thin film made of liquid crystal.
ある請求項13記載の光学変調素子。14. The optical modulator according to claim 13, wherein the liquid crystal is a chiral smectic liquid crystal.
る請求項12記載の光学変調素子。15. The optical modulation device according to claim 12, wherein the third thin film is a thin film made of a liquid crystal.
ある請求項15記載の光学変調素子。16. The optical modulation device according to claim 15, wherein the liquid crystal is a chiral smectic liquid crystal.
膜である請求項12記載の光学変調素子。17. The optical modulation device according to claim 12, wherein the second thin film is a thin film made of a polymer liquid crystal.
1.6μｍである請求項12記載の光学変調素子。18. The film thickness of the first and third thin films is 1.2 to 1.2.
13. The optical modulation device according to claim 12, which is 1.6 μm.
ッターによって偏光された光線に複屈折を生じさせる第
１の状態と該光線に複屈折を生じさせない第２の状態と
を生じる薄膜であって、該薄膜が該第１の状態を生じて
いる時に、1/2波長板として機能する膜厚である第１の
薄膜、 c2.前記第１の薄膜の第１の状態を通過した光線に複屈
折を生じさせ、前記第１の薄膜の第２の状態を通過した
光線に複屈折を生じさせない薄膜であって、前記第１の
薄膜が前記第１の状態である時に1/4波長板として機能
する膜厚である第２の薄膜、及び、 c3.前記第２の薄膜を通過した光線を反射し、該光線を
再度該第２の薄膜に入射させる反射手段、を有する光学
変調素子、 並びに、 前記第１の薄膜に電界を印加する電界印加手段、を有す
る表示装置。19. A light source for generating an indefinitely polarized light beam, b. A polarizing beam splitter c1. A first light source for generating birefringence in a light beam polarized by the polarizing beam splitter in response to an applied voltage. A first thin film that produces a state and a second state that does not cause birefringence in the light beam, the first film having a thickness functioning as a half-wave plate when the thin film produces the first state. C2. A thin film that causes birefringence in light rays that have passed through the first state of the first thin film and does not cause birefringence in light rays that have passed through the second state of the first thin film. A second thin film having a thickness functioning as a quarter-wave plate when the first thin film is in the first state, and c3. Reflecting light passing through the second thin film, An optical modulation element having a reflection unit for re-entering the light beam on the second thin film; and Display device having a field applying means for applying an electric field to said first thin film.
る請求項19記載の表示装置。20. The display device according to claim 19, wherein said first thin film is a thin film made of liquid crystal.
ある請求項20記載の表示装置。21. The display device according to claim 20, wherein the liquid crystal is a chiral smectic liquid crystal.
膜である請求項19記載の表示装置。22. The display device according to claim 19, wherein said second thin film is a thin film made of a polymer liquid crystal.
電極を有する請求項19記載の表示装置。23. The display device according to claim 19, further comprising a pair of electrodes disposed so as to sandwich the first thin film.
極間に一方極性パルスと他方極性パルスとを選択的に印
加する電界印加手段を有する請求項23記載の表示装置。24. The display device according to claim 23, wherein said electric field applying means includes an electric field applying means for selectively applying one polarity pulse and another polarity pulse between said pair of electrodes.
ある請求項19記載の表示装置。25. The display device according to claim 19, wherein the first thin film has a thickness of 1.2 to 1.6 μm.
ある請求項19記載の表示装置。26. The display device according to claim 19, wherein said second thin film has a thickness of 0.6 to 0.8 μm.
Priority Applications (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2074654A JP2851906B2 (en) | 1990-03-23 | 1990-03-23 | Optical modulation element and display device |
| EP91104574A EP0448124B1 (en) | 1990-03-23 | 1991-03-22 | Optical modulation device and display apparatus |
| DE69128553T DE69128553T2 (en) | 1990-03-23 | 1991-03-22 | Optical modulation device and display device |
| AT91104574T ATE161976T1 (en) | 1990-03-23 | 1991-03-22 | OPTICAL MODULATION DEVICE AND DISPLAY DEVICE |
| CA002038869A CA2038869C (en) | 1990-03-23 | 1991-03-22 | Optical modulation device and display apparatus |
| US08/266,320 US5392142A (en) | 1990-03-23 | 1994-06-27 | Display apparatus with chiral smectic and polymer liquid crystal films, each having birefringent first state and not birefringent second state |
| US08/346,282 US5568283A (en) | 1990-03-23 | 1994-11-21 | Optical modulation device and display apparatus with three birefringent films each acting as a half waveplate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2074654A JP2851906B2 (en) | 1990-03-23 | 1990-03-23 | Optical modulation element and display device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03274022A JPH03274022A (en) | 1991-12-05 |
| JP2851906B2 true JP2851906B2 (en) | 1999-01-27 |
Family
ID=13553433
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2074654A Expired - Fee Related JP2851906B2 (en) | 1990-03-23 | 1990-03-23 | Optical modulation element and display device |
Country Status (6)
| Country | Link |
|---|---|
| US (2) | US5392142A (en) |
| EP (1) | EP0448124B1 (en) |
| JP (1) | JP2851906B2 (en) |
| AT (1) | ATE161976T1 (en) |
| CA (1) | CA2038869C (en) |
| DE (1) | DE69128553T2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100816337B1 (en) * | 2001-10-08 | 2008-03-24 | 삼성전자주식회사 | Liquid crystal display |
Families Citing this family (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2851906B2 (en) * | 1990-03-23 | 1999-01-27 | キヤノン株式会社 | Optical modulation element and display device |
| JP2994814B2 (en) * | 1990-11-09 | 1999-12-27 | キヤノン株式会社 | Liquid crystal device |
| US5589966A (en) * | 1993-05-11 | 1996-12-31 | Mitsui Petrochemical Industries, Ltd. | Antiferroelectric liquid crystal light modulation device |
| WO1995015513A1 (en) * | 1993-11-30 | 1995-06-08 | Isis Innovation Limited | Improvements relating to spatial light modulators |
| US6380997B1 (en) * | 1995-04-07 | 2002-04-30 | Colorlink, Inc. | Achromatic polarization inverters for displaying inverse frames in DC balanced liquid crystal displays |
| SG49972A1 (en) | 1995-07-19 | 1998-06-15 | Sony Corp | Reflective guest host liquid-crystal display device |
| US5726723A (en) * | 1996-01-31 | 1998-03-10 | Technology Research International Corporation | Sub-twisted nematic liquid crystal display |
| GB2313920A (en) * | 1996-06-07 | 1997-12-10 | Sharp Kk | Diffractive spatial light modulator and display |
| KR20000064299A (en) * | 1996-09-02 | 2000-11-06 | 야스카와 히데아키 | Liquid crystal panel and electronic device using it |
| GB2318878A (en) * | 1996-10-31 | 1998-05-06 | Sharp Kk | Reflective liquid crystal device |
| US6313893B1 (en) * | 1996-12-27 | 2001-11-06 | Duke University | Compensation for DC balancing of liquid crystal displays |
| GB2330422A (en) * | 1997-10-17 | 1999-04-21 | Sharp Kk | Reflective liquid crystal device |
| JP2000347177A (en) * | 1999-03-29 | 2000-12-15 | Minolta Co Ltd | Display optical device and projector display device using the same |
| US6233084B1 (en) * | 1999-07-28 | 2001-05-15 | Hewlett-Packard Company | Optical display system including an achromatized ferroelectric light valve |
| JP3980823B2 (en) * | 1999-11-06 | 2007-09-26 | 三星電子株式会社 | Display apparatus and method using a single liquid crystal display panel |
| GB2356462A (en) * | 1999-11-16 | 2001-05-23 | Sharp Kk | Optical properties of spacers in liquid crystal devices |
| KR100385879B1 (en) * | 2000-10-26 | 2003-06-02 | 엘지전자 주식회사 | Optical System Of Liquid Crystal Projector |
| JP2002268014A (en) * | 2001-03-13 | 2002-09-18 | Olympus Optical Co Ltd | Image display device |
| US20030089956A1 (en) * | 2001-09-27 | 2003-05-15 | Allen Richard Charles | Polarization rotators, articles containing the polarization rotators, and methods of making and using the same |
| JP5154418B2 (en) | 2005-08-19 | 2013-02-27 | リアルディー インコーポレイテッド | Stereoscopic eyewear |
| US7792403B1 (en) | 2005-09-08 | 2010-09-07 | Infinera Corporation | Adiabatic polarization converter |
| DE602005023075D1 (en) * | 2005-11-09 | 2010-09-30 | Tte Technology Inc | BIT WEIGHT ASSIGNMENT IN A DISPLAY DEVICE |
| CN101339321B (en) * | 2007-07-06 | 2010-05-26 | 深圳Tcl工业研究院有限公司 | LCD device |
| US7565041B2 (en) * | 2007-10-26 | 2009-07-21 | Infinera Corporation | Symmetric optical circuit with integrated polarization rotator |
| CN113495380B (en) * | 2020-03-18 | 2023-12-01 | 瀚宇彩晶股份有限公司 | Reflective liquid crystal display panel |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61134736A (en) * | 1984-12-05 | 1986-06-21 | Sharp Corp | Smectic c* liquid crystal display apparatus |
| JPS6270407A (en) * | 1985-09-25 | 1987-03-31 | Fuji Photo Film Co Ltd | Preparation of orientated film |
| JPS6275418A (en) * | 1985-09-27 | 1987-04-07 | Alps Electric Co Ltd | Liquid crystal element |
| SE8504762D0 (en) * | 1985-10-14 | 1985-10-14 | Sven Torbjorn Lagerwall | FERROELECTRIC LIQUID CRYSTAL DEVICES |
| JPS62244019A (en) * | 1986-04-17 | 1987-10-24 | Seiko Epson Corp | Liquid crystal electro-optical device |
| JPS62265627A (en) * | 1986-05-13 | 1987-11-18 | Seiko Epson Corp | Liquid crystal display device |
| EP0298602A1 (en) * | 1987-06-09 | 1989-01-11 | Mitsubishi Kasei Corporation | Electro-optic device using ferroelectric liquid crystal |
| JPH01178927A (en) * | 1987-12-29 | 1989-07-17 | Idemitsu Kosan Co Ltd | Liquid crystal display element |
| JPH01209480A (en) * | 1988-02-18 | 1989-08-23 | Kawasaki Heavy Ind Ltd | Liquid crystal panel and image projecting device using it |
| US5272552A (en) * | 1988-05-11 | 1993-12-21 | Canon Kabushiki Kaisha | Optical modulation device and method using modulation layer of helical polymer liquid crystal having a helical chiral smectic C phase |
| US5066107A (en) * | 1988-06-16 | 1991-11-19 | Canon Kabushiki Kaisha | Liquid crystal display medium, liquid crystal display method and liquid crystal display apparatus for outputting color images |
| US5033825A (en) * | 1988-12-26 | 1991-07-23 | Kabushiki Kaisha Toshiba | Ferroelectric liquid crystal display device having equalizing means |
| US5132826A (en) * | 1989-10-30 | 1992-07-21 | The University Of Colorado Foundation, Inc. | Ferroelectric liquid crystal tunable filters and color generation |
| US5168381A (en) * | 1989-10-30 | 1992-12-01 | University Research Corporation | Smectic liquid crystal devices using SSFLC and electroclinic effect based cells |
| JP2851906B2 (en) * | 1990-03-23 | 1999-01-27 | キヤノン株式会社 | Optical modulation element and display device |
-
1990
- 1990-03-23 JP JP2074654A patent/JP2851906B2/en not_active Expired - Fee Related
-
1991
- 1991-03-22 EP EP91104574A patent/EP0448124B1/en not_active Expired - Lifetime
- 1991-03-22 AT AT91104574T patent/ATE161976T1/en not_active IP Right Cessation
- 1991-03-22 DE DE69128553T patent/DE69128553T2/en not_active Expired - Fee Related
- 1991-03-22 CA CA002038869A patent/CA2038869C/en not_active Expired - Fee Related
-
1994
- 1994-06-27 US US08/266,320 patent/US5392142A/en not_active Expired - Lifetime
- 1994-11-21 US US08/346,282 patent/US5568283A/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100816337B1 (en) * | 2001-10-08 | 2008-03-24 | 삼성전자주식회사 | Liquid crystal display |
Also Published As
| Publication number | Publication date |
|---|---|
| DE69128553D1 (en) | 1998-02-12 |
| DE69128553T2 (en) | 1998-05-20 |
| CA2038869C (en) | 1995-09-05 |
| US5392142A (en) | 1995-02-21 |
| EP0448124A2 (en) | 1991-09-25 |
| EP0448124A3 (en) | 1992-08-05 |
| JPH03274022A (en) | 1991-12-05 |
| CA2038869A1 (en) | 1991-09-24 |
| US5568283A (en) | 1996-10-22 |
| EP0448124B1 (en) | 1998-01-07 |
| ATE161976T1 (en) | 1998-01-15 |
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